title: Image thresholding techniques for localization of sub-resolution fluorescent biomarkers.
abstract: In this article, we explore adaptive global and local segmentation techniques for a lab-on-chip nutrition monitoring system (NutriChip). The experimental setup consists of Caco-2 intestinal cells that can be artificially stimulated to trigger an immune response. The eventual response is optically monitored using immunofluoresence techniques targeting toll-like receptor 2 (TLR2). Two problems of interest need to be addressed by means of image processing. First, a new cell sample must be properly classified as stimulated or not. Second, the location of the stained TLR2 must be recovered in case the sample has been stimulated. The algorithmic approach to solving these problems is based on the ability of a segmentation technique to properly segment fluorescent spots. The sample classification is based on the amount and intensity of the segmented pixels, while the various segmenting blobs provide an approximate localization of TLR2. A novel local thresholding algorithm and three well-known spot segmentation techniques are compared in this study. Quantitative assessment of these techniques based on real and synthesized data demonstrates the improved segmentation capabilities of the proposed algorithm.
authors.affiliation: Laboratory of Integrated Systems (LSI), Swiss Federal Institute of Technology, EPFL, Lausanne, Switzerland.
authors.forename: Julien
authors.initials: J
authors.lastname: Ghaye
authors.forename: Madhura Avinash
authors.initials: MA
authors.lastname: Kamat
authors.forename: Linda
authors.initials: L
authors.lastname: Corbino-Giunta
authors.forename: Paolo
authors.initials: P
authors.lastname: Silacci
authors.forename: Guy
authors.initials: G
authors.lastname: Vergères
authors.forename: Giovanni
authors.initials: G
authors.lastname: De Micheli
authors.forename: Sandro
authors.initials: S
authors.lastname: Carrara
mesh_terms: D015415:Biomarkers; D018938:Caco-2 Cells; D005455:Fluorescent Antibody Technique; D006801:Humans; D007091:Image Processing, Computer-Assisted; D051195:Toll-Like Receptor 2 / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D015415:Biomarkers; C495342:TLR2 protein, human; D051195:Toll-Like Receptor 2
keywords: Caco-2 cell line; adaptive thresholding; fluorescence microscopy; image processing; nutrition; toll-like receptor 2